1. Field of the Invention
A connector arrangement is provided for supplying electric power to a three-phase motor to produce motor operation in either a delta mode or a star mode, use being made of modular units that are removably mounted within a chamber contained in an outer frame that is secured to the motor housing. A power supply module arranged within the chamber includes a main receptacle containing a stack of terminal blocks having bus bars that transmit to the motor windings three-phase power that is supplied either by external power supply lines that extend into the chamber though openings contained in the side walls of the outer frame, or from an inverter arranged externally of the outer frame. Auxiliary receptacles are removably connected with the external surface of the main receptacle for monitoring the operating condition of the motor, or for controlling a motor operation, such as braking.
2. Description of Related Art
Various motor control arrangement have been proposed in the prior art for operating three-phase electric motors in various operating modes, such as in the delta mode or the star mode. Such connection devices are known per se but they usually conform to the standards of only one specific connection circuit, so it is necessary to provide various connection devices for use with various different control circuits. The object of the present invention is to eliminate this problem, use being made of interchangeable modules that may be mounted in the frame that is attached to the motor housing.
The modular design may be mentioned as a special advantage of this embodiment, making it possible, starting from a basic module, to conform to a wide variety of connection situations through optional expansion housings. According to this, a basic power receptacle is provided to receive preferably a stack of terminal blocks aligned together, preferably on one or more outer sides with coupling means for attaching one or more optional auxiliary housings having corresponding coupling means.
The terminal blocks allow an especially simple and variable design easily in the manner of series terminals. The optional modular design also allows simple adaptability to different connection situations.
Preferably at least one of the auxiliary housings is provided with terminal contacts for connecting signal conductors, which may be designed in any connection technology, for example, with the arrangement of plug connectors or socket connectors on a circuit board being preferable but not obligatory.
The invention also creates a connection device for connecting electric conductors to an electric motor which has a housing with a box-shaped frame for holding the motor connection device and where the connection device has a design for optional connection of conductors to the terminal of an electric motor in at least two different types of circuits, in particular for optional connection of conductors to the terminal of an electric motor by means of a delta connection or by means of a star connection. This creates a connection device with which at these two controls are optionally implementable in the simplest possible manner through a corresponding use of the given connection possibilities.
At least one of the auxiliary housings is especially preferably provided with a bus bar having three terminal contacts for forming a neutral point of a star connection.